People commonly have their financial resources spread across accounts at multiple financial institutions, for example, a checking account at a local bank, a retirement account through an employer, and a money market through a brokerage firm. Aggregation systems, such as the iFinity Platform™ by Yodlee, Inc.™, help individuals to manage their assets by collecting and consolidating personal account data from multiple sources into a single, consolidated interface. On-line bill payment systems allow a user to negotiate checks over the Internet.